Bromate-perhydrate fixing composition



2,809,150 BROMATE-PERHYDRATE FIXING COMPOSITION Everett Goodrich McDonough, New York, N. Y., assignor to The Procter & Gamble Company, Ivorydale, Olno, a corporation of Ohio No Drawin". Application February 26, 1951, Serial N0. 212,330

13 Claims. (Cl. 167- -87.1)

This invention relates to an improved fixing composition suitable for use in processes involving changing the configuration of keratin-containing substances; more particularly, the invention concerns the provision of a new composition for use as a fixing agent in the cold permanent waving of hair. V

In permanent waving of hair, particularly in the process which has come to be known as cold permanent waving, the hair, while curled on a mandrel, is allowed to react with a mercaptan solution whereby at least a part of the keratin disulfide (cystine) of the hair is reduced to produce sulfhydryl compounds of keratin (cysteine). Sub sequently, while the hair is held in the desired configuration, disulfide groups thereof are restored by treatment with an aqueous solution of an oxidizing agent. Such treatment is generally, but not necessarily, preceded by a liberal rinsing with water. The treatment with the oxidizing agent is designed to set or fix the hair in the configuration in which it is held on the mandrel and otherwise restore the hair to the normal condition it possessed prior to the mercaptan treatment, not only with respect to its physical and chemical properties but also with respect to the feel of the hair and its odor. Further, the treatment should render residual mercaptan inactive so that there is no subsequent tendency for'the hair to relax or lose the configuration or wave. This treatment step is sometimes referred to as the fixing or neutralizing step and the agents used arequite commonly referred to synonymously as oxidizing agents, fixing agents, neutralizers or neutralizing agents. Obviously an important factor in the success of a cold permanent wave is the choice and use of the neutralizer.

The mercaptan compositions which are employed for the purpose of reducing the keratin of hair form no part of the present invention; the compositions which I prefer are fully disclosed in my Australian Patent 117,071. Moreover, the manner in which my fixing agents are used is not a part of the invention. The usual methods recommended in home waving kits and methods employed professionally may be employed without departing from the spirit of the invention. a

, Potassium bromate has long been a preferredneutralizing agent, particularly for home waving use, since it can be. packaged in solid form and is relatively non-hygroscopic and stable against decomposition during storage. Moreover, it can be packaged and used without dangerous fire hazard. However, alkali metal bromates, such as potassium bromate, in water solution act with sluggishness in their oxidizing action. As a result large excesses of potassiumbromate have been employed in the past to effect the desired oxidation of reduced keratin. Even though large excesses are used, the reaction proceeds at such a slow rate that in the absence of care during the neutralizing step the danger of incomplete oxidation of cysteine to cystine is a distinct possibility, allowing relaxationor loss of the wave in a short time after treatment as the oxidation goes toward completion subsequently, through exposure to oxygen of the air. The exact ex- Patented Oct. 8, 1 957 duced portion of the hair with the oxidizing agentis prevented.

p The necessary use of large excesses of alkali metal bromates to achieve satisfactory waving results withrthese compounds presents an additional problem in that the concentrations which have been normally recommended for satisfactory results involve the use of an amount of bromate which is toxic to an undesired degree if taken internally, and there have been instances of accidental internal consumption.

Attempts have been made to overcome the sluggish oxidative action of the bromates by the addition of materials which impart an acid character to the aqueous solution of the composition prepared for use. Such materials include ammonium chloride and sodium dihydrogen orthophosphate, but the addition of such acid buffering agents renders the bromate less stable against decomposition and the resultant liberation of objectioanble fumes of either bromine or bromine oxides. Special packaging of mechanical mixtures of the bromate and acid buffering agent has been required to avoid absorption of moisture which is'conducive to such decomposition. In addition a solution of a fixing agent ofthis nature cannot always be relied on to removeresidual mercaptan, and as a result the hair may retain the odor of mercaptan and the wave may relax in time.

It is an object'of the present inventionto' provide as a neutralizing agent for use in permanent waving an activated bromate, such as an'alkali metal bromate,.which can be packaged in solid form and which is rapid. in its oxidation of reduced keratin when employed in aqueous solution. A further object is to'provide an activated alkali metal bromate neutralizing agent which effectively removes residual mercaptan odor from the hair. Another object is to provide an activated bromate neutralizing-agent which reacts to a markedly greater degree with reduced hair to reformdisulfide linkages, thereby minimizing relaxation of the imparted wave. Another object is to provide an activated alkali metal bromate neutralizing agent which has improved rate of solubility in water, which, in the concentrations required for use, has desirably low toxicity if taken internally, which is non-irritating to the skin, and which possesses no objectionable odors per se and gives rise to none.

I have discovered that the activity and suitability of the alkali metal bromates as neutralizing agents can be materially enhanced by admixing therewith a small amount, as more fully hereinafter described, of atleast one activating agent selected from that group of solid, water-soluble, inorganic, alkali metal salts which may be considered as perhydrates, that is inorganic alkali metal salts which. in aqueous solution generate hydrogen peroxide. Probably the best known examples of compounds of this group are the alkali metalperborates such as sodium perborate whose chemical formula has been written asNaBOzl-IzOz (sometimes referred to as the monohydrate) and NEIBO2.3H2O2 (sometimes referred to as the tetrahydrate). Other compounds coming in the above group are the alkali metal perpyrophosphates, e. g. K4P2O7.2H2O2, the alkali metal percarbonates, e. g. 2Na2COs.3H2O2, and the alkali metal perborosilicates, e. g. NaBOz.NazSi0aI-Iz0z. Of course,'thes e activating agents are themselves oxidizing agents but they possess serious handicaps which render them unsuitable for use alone as neutralizing agents in the hair art. In the first place they are relatively unstable at temper-ate summer temperatures unless stored and packaged so as to exclude moisture. In addition such perhydrate compounds must be used with care'hecaus'e in aqueous solution they react substantially in the same manner as alkaline hydrogen peroxide and therefore tend to eifect undesirable hair bleaching. They also present serious fire hazard. These disadvantages of the per compounds are rendered unimportant in connection with their use in myinvention since the bromate is used in predominant proportion in the composition and is relied on as the primary source of oxygen. The perhydrate is in very minor proportion, primarily functioning as an activator for the bromate, and in the concentrations employed in actual use the amount not only is insufiicient to effect undesirable bleaching of the air but also is insufficient to effect complete reoxidation of the reduced keratin.

Whether the action of the activating agents of my compositions vvith the bromates is catalytic or synergistic when a solution of the composition is used is not known, but, as demonstrated in the examples below, their use in an amount which alone is insutficient to effect the desired oxidation activates the bromate to such a degree that one obtains a rate and a completeness of oxidation that markedly exceeds the rate and completeness observed when either the bromate or perhydrate is used alone in comparable concentration.

The addition of alkali metal per compound in accordance with my invention so markedly activates the alkali metal bromate and increases its elfectiveness that the amount of bromate necessary for adequate reoxidation of the reduced keratin in a single hair waving job can be reducedbelow the level at which toxicity of the solution employed is a serious problem.

In'addition, the perhydrate imparts to the solution a desirable pH value which is not significantly difierent from that of the mercaptan solution, i. efpH 9.2-9.5, and thus, in contrast to the result of using an acidbuflfered bromate, any swelling or increase in porosity of the hair caused by the alkaline condition of the mercaptan lotion is not decreased prior to thorough diffusion of the neutralizing agent throughout the hair. Thus'the very agent which supplies the alkaline pH activates the bromate so that it is effective at the desirable pH range.

'Because alkali metal bromates, such as potassium bromate, exhibit toxic characteristics if taken internally in large amount I prefer to use in one complete permanent wave for a human subject a solution, usually'about 1000 cc., containing not substantially more than 15 grams bromate. Accidentalinternal consumption of such'solutioninvolves little or no serious danger. Other alkali metal bromates, such as sodium bromate, in substantially equivalent oxidizing amounts can be employed. In combination with such quantity of bromate, as little as 0.1 gram of sodium'perborate monohydrate, for example, shows such'an activating effect that the resulting composition is far superior in its oxidative action to 30' grams of bromate alone. Larger quantities of perborate show an improved result, but with my preferred optimum of about grams of potassium bromate per 1000cc. of neutralizing solution I prefer the addition of about 2 grams of sodium perborate monohydrate. Faster oxidizing action will be noted with increase in the proportion of perborate, but as the amount increases hair bleaching becomes a greater possibility, and to be on the safe' side I prefer to limit the amount of perborate to a maximum of 4 grams. When such amount of perborate is employed, the amount of bromate can be reduced to about 8 grams without significantly affecting the performance of the mixture as a neutralizing agent.

Substantially the same proportions of perhydrate to bromate are suitable for use when other than the alkali metal perborates are employed, but obviously in the case of those compounds, such as the perpyrophosphates which contain a lower weight percentage of available hydrogen peroxide, somewhat higher proportions may be tolerated 'wi'thbut risking undesirable hair' bleaching effect. Thus in a composition containing from about 8 grams to about 15 grams of bromate for use in about 1000 cc. of solution the amount of perhydrate used should preferably be such that the potential hydrogen peroxide content is in the range of about 0.03 grams to 1.4 grams by weight. The solutions preferred for use in the fixing or neutralizing step therefore contain about 0.8% to about 1.5% bromate, and about 0.003% to about 0.14% potential hydrogen peroxide in the perhydrate.

I have also found that the addition of a calciumsequestering alkali metal polyphosphate, such as sodium tripolyphosphate, to the composition imparts certain desirable features without detracting in any way from the unique properties already possessed by my mixture. The outstanding virtue of the addition of such polyphosphates resides in the increase in the rate at which the entire mixture dissolves in water. For example, it has been found that under standardized conditions of stirring about 71 minutes are required to completely dissolve a mixture of 10 grams potassium bromate and 2 grams sodium perborate in about 1000 cc. of distilled water at 70 F., whereas only about 40 /2 minutes are required to dissolve the same mixture to which has been added 5 grams of sodium tripolyphosphate. At F. the time to dissolve the latter mixture is about 10% minutes. Similar improvement in solubility rates have been noted when hard water containing the equivalent of 20 grains per gallon of CaCOs is used.

The addition of the poly phosphate also has the advantageous characteristic of reducing the loss of oxidizing power of both the solid mixture and its aqueous solution during storage and handling. Another desirable advantage possessed by sodium tripolyphosphate particularly is the additional buffering action in the desired alkaline pH range, that is, around pH 9.2 to pH 9.5. Moreover, in the case of the treatment of hair which contains lime soap accumulations due to shampooing in'hard water, the calcium sequestering polyphosphate aids" in the wetting out and penetration of the solution into the hair, thereby enabling more complete reoxidation. While a small proportion such as one part of sodium tripolyphosphate to a mixture containing from about 8 toabout 15 parts of bromate imparts improvements above noted to some degree, and as much as 10 parts of the phosphate may be beneficially employed, I have found that theuse of about 5 parts of sodium tripolyphosphate is preferred' Thus in my preferred mixture which is intended for the preparation of about 1000 cc. ofsolutionfto be used in the neutralizing of one head wave, I prefer to use 10 grams potassium bromate, 2 grams sodium'perbora'te monohydrate, and 5 grams sodium tripolyphosphate.

Compositions of the present invention have been employ'ed'in actual hair waving operations on human subjects and such tests'have in every instance proved the superiority of the compositions to bromate alone or acid buffered bromate. The waved hair resulting from the use of my activated bromate had no residual mercaptan odor, possessed excellent resistance toward relaxation of the wave, was normal in feel, appearance and odor, and was satisfactory in every respect.

'The following examples will set forth more fully the manner in which my invention may be practiced, but it is to be understood that the examples are given for illustrative purposes only and that the scope of the invention is to be measured by the appended claims.

Example 1.The hair on the head of a living human subject, moistened with a 5% solution of thioglycolic acid ammdniacal to a pH of about 9.2, was wrapped on solid rods and suitably fastened, then saturated with the solution ofthioglycolic acid. The hair was allowed to remain in, this saturated state while wrapped on the curling rod until sufiicient timehad elapsed for the formation of definite wave ridges when a strandofthe hair was uncoiled. At this time the hair was freely rinsed with water at 100-l20 F., and such rinsing was con- :tinued until approximately 12 gallons of water had been used. Following the rinse, one half of a solution at '100-l20 F. prepared by adding to about one liter of Eheated water 17 grams of a mechanical mixture composed of 10 parts potassium bromate, 2 parts sodium perborate'monohydr ate, and parts sodium tripolyphosphate was poured over the hair, caught in a suitable receptacle, and reapplied with cotton or other applicator continuously for about 5 minutes. The used portion of the fixing solution was discarded. i

The hair was then unwound from the rods and the remaining one half of the fixing solution was poured through the hair repeatedly over a period ,of time of :about 3 minutes thorough contact of' the hair with the solution being effected. The hair was then thoroughly 'rinsed, set and dried. The .wave characteristics noted were excellent and the wave was not relaxed appreciably one month later. Moreover, the wave hair did not have the odor of residual mercaptan as did a wave given in the same way but with an acid bromate fixative employed in place of the fixative described and used above.

Substantially the same advantageous results were obtained by use of a comparable fixing composition prepared with sodium bromate instead of potassium bromate in this example.

Substitution of either 3 parts of sodium perpyrophosphate or of 2 parts sodium percarbonate as the activator for 2 parts sodium perborate in the above formulation yields a fixing-solution which possesses advantages similar to those shown above.

Example 2.Three human subjects, one having average hair texture and two having fine hair texturewere each given permanent waves, half of the hair being waved with a commercially available ammonium thioglycolate waving lotion and fixative solution, and the other half being waved with the same waving lotion and a solution of a neutralizer prepared in accordance with the present invention and containing about 1% potassium bromate and 0.2% sodium perborate monohydrate. Treatment procedure in each case was comparable and conducted substantially as indicated in Example 1 (half portions of fixing solution being employed) so that differences between the half head waves in the case of each subject reflected the difference in the neutralizing agent.

On the average the initial results indicated better wave characteristics in the case where the solution of my invention was employed. No residual mercaptan odor was possessed by this hair whereas that neutralized with the use of the commercial neutralizer possessed a distinct odor. The average superiority noted initially with regard to wave character persisted over a two months period during which the condition of the hair of each subject was checked one week, one month, and two months after administration of the wave.

Example 3.-Three human subjects, one having coarse hair texture and two having fine hair texture were each given half head permanent waves as in Example 2 except that the neutralizer coming within the invention consisted of an aqueous solution containing 1% potassium bromate, 0.2% sodium perborate monohydrate, and

0.25% sodium tripolyphosphate.

Superiority of the wave neutralized with the use of the solution of the invention as regards wave relaxation and character was clearly evident initially and throughout the two month period during which periodic visual checks of the waves were made. The mercaptan odor possessed by the hair neutralized with the commercial preparation was not possessed by the hair neutralized .With the solution of the invention and in all respects .6 superiority was more pronounced thanin the case of the comparison ofExample 2. 1

The action'of sodium bromate as a neutralizing agent for reduced hair is also enhanced by the addition of a perhydrate in accordance with the invention, increased speed and completeness of oxidation beingnoted by the use of an amount of sodium perborate monohydrate which is equal to one-tenth the amount of sodium bromate.

Example 4.Three human subjects, one having fine hair texture and two having average hair texture were each given half-head permanent waves as in. Example 2 except that the neutralizer coming within. the invention consisted of an aqueous. solution containing 1% potassium bromate, 0.2% sodium perborate monohydrate, and 0.5% sodium'tripolyphosphate.

Initial wave results indicated superior wave characteristics with no residual odor when the neutralizer of the invention was employed. A distinct residual odor was observed in the case of the hair neutralized with the commercial product.

Throughout the two month. period during which periodic visual checks of the waves were made, the hair neutralized with the product of the invention showed markedly better .wave characteristics. and less relaxation than the hair fixed with the commercialrproduct. v

The compositions of my invention as fully set forth above can be mechanically mixed "by means of machinery well known in the art, and when packaged for incorporation in home waving kits they can be enclosed in an envelope or in a soluble container such as a gelatin capsule Other types of containers can be employed and the composition can be compressed into tablet form if desired. Ordinarily the amount so packaged is sufiicientto enable the preparation of 1000 cc. or about one quart of a solution containing from about 8 to about 15 grams of the alkali metalbromate. Such amount is adequate for the fixing of-one complete wave, but smaller amounts or greater amounts may be packaged depending on. whether the neutralizing agent is designed for use in an end curl wave or in multiple waves. In any case the amountof water to which the selected amount of neutralizing agent is added is adjusted to give a solution containing from about 0.8 to about 1.5 percent of alkali metal bromate, ratios of other constituents of the neutralizing composition relative to the bromate being within the ranges given above.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. A composition suitable for use, when in aqueous solution, in the reoxidation of reduced keratin resulting from treatment thereof with an alkaline mercaptan solution, comprising essentially in admixture from about 8 to about 15 parts by weight of alkali metal bromate and, as an oxidative activator therefor, alkali metal perhydrate which in aqueous solution generates hydrogen peroxide, said alkali metal perhydrate having a potential hydrogen peroxide content from about 0.03 parts to 1.4 parts by weight and being present in sufiicient amount in the mixture to impart to an alkaline aqueous solution thereof containing from about 0.8 to about 1.5 percent alkali metal bromate an eifectiveness in speed and completeness of reoxidation of reduced keratin greater than that of either constituent.

2. The composition of claim 1 in which the metal bromate is potassium bromate.

3. The composition of claim 1 in which the metal bromate is sodium bromate.

4. The composition of claim 1 in which the alkali metal perhydrate is sodium perborate.

5. The composition of claim 1 in which the metal perhydrate is sodium perpyrophosphate.

6. The composition of claim 1 in which the metal perhydrate is sodium perearbonate.

7. A composition suitable for use, when in aqueous solution, in reoxidizing hair after reduction with meralkali alkali alkali alkali captan-:solution.having .a pH of about 9.2 to 9.5, com: prising essentially in admixture from about 8 to about '15 parts by weight of alkali metal bromate, alkali metal perhydrate which in aqueous solution generates hydrogen peroxide, the amount of perhydrate being such that the potential hydrogen peroxide content thereof is from about 0.03 part to 1.4 parts by weight, and from about 1 to about 10 parts by weight of alkali metal calcium-sequestering polyphosphate, said alkali metal perhydrate being in sufficient amount in the mixture to impart .to an aqueous solution thereof containing from about 0.8 to about 1.5 percent alkali metal bromate a pH not significantly different from that of the mercaptan and an effectiveness in speed and completeness of reoxidation which is greater than that of any constituent, and said alkali metal polyphosphate being in sufiicient amount to effect substantial increase in the rate of solution of the mixture ofbromate and perhydrate in water.

8. The composition of claim 7 in which the alkali metal bromate is potassium bromate, in which the alkali metal perhydrate is sodium perborate, and in which the alkali metal polyphosphate is sodium tripolyphosphate.

9. The composition of claim 8 in which the weight ratio of constituents is about 10 parts potassium bromate, about 2 parts sodium perborate, and about 5 parts sodium tripolyphosphate.

10. A composition suitable for use, when in aqueous solution, in the safe, effective and fast re-oxidation of reduced keratin resulting from treatment thereof with, an alkaline mercaptau solution, comprising essentially in admixture from about 8 to about 15 parts by weight of crystalline alkali metal bromate and as an oxidative activator therefor from about 0.03 to about 1.4 parts by weight of hydrogen peroxide in the form of a crystalline alkali metal perhydrate, said perhydrate being in sufficient amount in the mixture to impart to an aqueous solution thereof containing from about 0.8% to about 1.5% of said bromate and not more than 1.4% hydrogen peroxide, an alkaline pH not significantly ,diflerent from that of the mercaptan solution, and an effectiveness in speed and completeness of reoxidation of reduced keratin greater than that of either constituent.

.1 The' ompqsi ien f cl im 10 to wh h beenatldedtrern about. 1 to ab ut par s y Weight of alkali metal calcium-sequestering polyphosphate. i

12. A neutralizer composition for use in setting of mercaptan-relaxed hair in cold waving of the latter, comprising an alkali metal bromate and an alkali metal perborate, the perborate being present in an amount ranging from about 76% to about 33 /3% by weight of the sum of the bromate and perborate.

13. A neutralizer solution for use 'in setting of relaxed hair in the cold waving thereof, comprising a dilute aqueous solution of an alkali metal bromate and an alkali metal perhydrate, said solution containing from about 0.8% to about 1.5% bromate, and perhydrate in amount such that the potential hydrogen peroxide content thereof is from about 0.003% to about 0.14%.

References Cited in the file of this patent UNITED STATES PATENTS 2,064,541 Hershman Dec. 15, 1936 2,166,363 MacMahon July 18, 1939 2,418,664 Ramsey Apr. 8, 1947 2,457,480 Lewis Dec. 28, 1948 2,469,414 Schechter May 10, 1949 2,540,494 Schwarz Feb. 6, 1951 FOREIGN PATENTS 200,375 Great Britain July 12, 1923 771,569 France Oct. 12, 1934 66,713 Austria Sept. 25, 1914 597,072 Great Britain Jan. 16, 1948 604,990 Great Britain July 14, 1948 518,576 Great Britain Mar. 1, 1940 OTHER REFERENCES DeNavarre: Cold wave fixative, Am. Perf. and Essential Oil Review, January 1950, page 21.

Drug and Cosmetic Ind., Permanent Waving, Sep- 0 ternber 1948, p. 377. 

1. A COMPOSITION SUITABLE FOR USE, WHEN IN AQUEOUS SOLUTION, IN THE REOXIDATION OF REDUCED KERATIN RESULTING FROM TREATMENT THEREOF WITH AN ALKALINE MERCAPTAN SOLUTION, COMPRISING ESSENTIALLY IN ADMIXTURE FROM ABOUT 8 TO ABOUT 15 PARTS BY WEIGHT OF ALKALI METAL BROMATE AND, AS AN OXIDATIVE ACTIVATOR THEREFOR, ALKALI METAL PERHYDRATE, WHICH IN AQUEOUS SOLUTION GENERATES HYDROGEN PEROXIDE SAID ALKALI METAL PERHYDRATE HAVING A POTENTIAL HYDROGEN PEROXIDE CONTENT FROM ABOUT 0.03 PARTS TO 1.4 PARTS BY WEIGHT AND BEING PRESENT IN SUFFICIENT AMOUNT IN THE MIXTURE TO IMPART TO AN ALKALINE AQUEOUS SOLUTION THEREOF CONTAINING FROM ABOUT 0.8 TO ABOUT 1.5 PERCENT ALKALI METAL BROMATE AN EFFECTIVENESS IN SPEED AND COMPLETENESS OF REOXIDATION OF REDUCED KERATIN GREATER THAN THAT OF EITHER CONSTITUENT. 